Grandfather clock



FIG. 1 is a left front perspective view of a grandfather clock showing my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a left front perspective view thereof with the door opened and the clock works omitted for ease of illustration of the mirrored rear wall of the clock casing. 

The ornamental design for a grandfather clock, substantially as shown and described. 